Radon, a naturally occurring and ubiquitous respiratory carcinogen, has been a focus for public health research and policy debate for nearly a century. This application requests two years of support for the preparation of a book-length monograph on radon and lung cancer, focusing on the linkages between scientific evidence on radon and the development of regulations and public policies to reduce risks to miners and the general population. The book will chronicle the advances in scientific understanding of the lung cancer risk associated with radon exposure and lay over this historical account the key public health and policy issues: I) protection of underground miners against exposure to unacceptable levels, including the very high exposures sustained in the early U.S. and other uranium mines during the "Cold War"; 2) the tension between the ethical imperative to protect the early miners and the need to carry out research on their risks; 3) the evolution of evidence-based regulations to lower exposures in mines; 4) approaches to compensating miners for radon-caused lung cancers; 5) recognition of the problem of indoor radon and the subsequent attempts to characterize its risks; 6) the role of expert committees in evaluating exposures and the use of quantitative risk assessment for this purpose; and 7) risk management approaches and their linkages to the scientific evidence. The Principal Investigator, Jonathan M. Samet, M.D., MS., has gained experience in each of these dimensions of the topic through his epidemiologic research on underground uranium miners in New Mexico, his clinical practice of pulmonary medicine in that state, and his participation in many key committees on radon and lung cancer, including chairing the Biological Effects of Ionizing Radiation (BEIR) VI Committee of the National Research Council. The team will also include Charlotte Gerczak, MbA., who has worked with Dr. Samet in developing several book-length manuscripts. The research team will collect materials from Dr. Samets extensive files, further literature searches, review of archives of the federal and state governments, and personal contacts with researchers, policy-makers, and involved political figures and advocates. Anticipated products from this effort include a published book-length manuscript and expanded chapters submitted to the peer reviewed literature. The lessons from the history of radon and lung cancer will remain as informative examples of the use of scientific evidence for public health protection for decades.